Touch sensor system and multiplexer thereof

ABSTRACT

A touch sensor system includes a touch panel having a plurality of touch sensing areas, at least one multiplexer and a touch controller. The touch controller, for controlling touch driving and sensing on the touch panel, includes a plurality of pins connected to the multiplexer via a plurality of touch control wires and touch sensing wires, wherein each of the pins is connected to one of the touch control wires or touch sensing wires. Each of the touch sensing wires transmits driving signals from the touch controller to a corresponding multiplexer to perform driving on one of the touch sensing areas, and transmits sensing signals from the touch sensing area to the touch controller. The touch controller controls the multiplexer to perform touch driving and sensing on the touch sensing areas in a specific order by triggering the touch control wires in an order.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a touch sensor system and a multiplexerthereof, and more particularly, to a multiplexer capable of reducing apin number of a touch controller in the touch sensor system.

2. Description of the Prior Art

In recent years, the touch sensing technology advances rapidly, and manyconsumer electronic products such as mobile phones, GPS navigatorsystems, tablets, personal digital assistants (PDA) and laptops areequipped with touch sensing functions. A conventional touch sensorsystem is composed of a touch panel and a touch integrated circuit (IC).The touch IC is capable of transmitting driving signals to the touchpanel and correspondingly receiving sensing signals from touch sensingareas on the touch panel.

Please refer to FIG. 1, which is a schematic diagram of a general touchsensor system 10. As shown in FIG. 1, the touch sensor system 10includes a touch panel 100 and a touch IC 102. The touch panel 100includes 9 touch sensing areas arranged in a 3×3 array. Each touchsensing area is connected to the touch IC 102 via a connecting wire anda contact. In such a situation, the touch IC 102 should include at least9 I/O pins for connecting with the touch sensing areas.

However, as the commercial requirements of larger touch panels increase,the number of touch sensing areas on a touch panel increases with thesize of the touch panel. To date, there may be hundreds or thousands oftouch sensing areas on a touch panel. For example, in a touch panelhaving touch sensing areas arranged in a 32×18 array, there are 576touch sensing areas on the touch panel. In such a situation, the touchIC should include at least 576 I/O pins for connecting with the touchsensing areas. The large number of I/O pins significantly increases thedie size of the touch IC, and thus increases the cost. The wire bondingquality is also reduced since the bonding pitch is limited. Thus, thereis a need for improvement over the prior art.

SUMMARY OF THE INVENTION

It is therefore an objective of the present invention to provide amultiplexer disposed between the touch controller and the touch panel,to reduce the pin number of the touch controller.

The present invention discloses a touch sensor system. The touch sensorsystem comprises a touch panel, at least one multiplexer and a touchcontroller. The touch panel comprises a plurality of touch sensingareas. The at least one multiplexer is coupled to the plurality of touchsensing areas on the touch panel. The touch controller, coupled to theat least one multiplexer, is used for controlling touch driving andsensing on the touch panel. The touch controller comprises a pluralityof pins connected to the at least one multiplexer via a plurality oftouch control wires and a plurality of touch sensing wires, wherein eachof the plurality of pins is connected to one of the plurality of touchcontrol wires or one of the plurality of touch sensing wires. Each ofthe plurality of touch sensing wires transmits driving signals from thetouch controller to a corresponding multiplexer among the at least onemultiplexer to perform driving on one of the plurality of touch sensingareas, and transmits sensing signals from the touch sensing area to thetouch controller. The touch controller controls the at least onemultiplexer to perform touch driving and sensing on the plurality oftouch sensing areas in a specific order by triggering the plurality oftouch control wires in an order.

The present invention further discloses a multiplexer used in a touchsensor system. The multiplexer is used for reducing a pin number of atouch controller of the touch sensor system. The touch controller isconnected to the multiplexer via a plurality of touch control wires anda plurality of touch sensing wires. The multiplexer comprises aplurality of switches, each of which comprises a first connectionterminal, a second connection terminal and a control terminal. The firstconnection terminal is coupled to the touch controller via one of theplurality of touch sensing wires. The second connection terminal iscoupled to a touch panel of the touch control system, and the touchpanel comprises a plurality of touch sensing areas. The controlterminal, coupled to one of the plurality of touch control wires, isused for receiving one of a plurality of control signals from the touchcontroller. Several of the plurality of switches connected to specifictouch sensing areas among the plurality of touch sensing areas receiveone of the plurality of control signals from a same touch control wireamong the plurality of touch control wires via the control terminal, andthe plurality of control signals is triggered in an order to allow theplurality of touch sensing areas to undergo touch driving and sensing ina specific order.

The present invention further discloses a method of reducing a pinnumber of a touch controller of a touch sensor system. The touch sensorsystem comprises a plurality of multiplexers coupled between the touchcontroller and a touch panel. The method comprises sequentiallytriggering a plurality of control signals to a plurality of touchcontrol wires of the multiplexers, and receiving a plurality of touchsensing signals from the multiplexers to the touch controller.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a general touch sensor system.

FIG. 2 is a schematic diagram of a touch sensor system according to anembodiment of the present invention.

FIG. 3 is a schematic diagram of an exemplary circuit structure of themultiplexer.

FIG. 4 is a waveform diagram of control signals on the touch controlwires.

FIG. 5 is a schematic diagram of another exemplary circuit structure ofthe multiplexer.

FIG. 6 is a schematic diagram of another touch sensor system accordingto an embodiment of the present invention.

FIGS. 7A and 7B are schematic diagrams of detailed circuit structures ofthe multiplexers.

FIG. 8 is a waveform diagram of control signals on the touch controlwires.

FIG. 9 is a waveform diagram of control signals on the touch controlwires according to another embodiment of the present invention.

FIG. 10 is a schematic diagram of a touch sensor system according to anembodiment of the present invention.

FIGS. 11A and 11B are schematic diagrams of detailed circuit structuresof the multiplexers.

FIG. 12 is a waveform diagram of control signals on the touch controlwires.

FIG. 13 is a flow chart of a process according to an embodiment of thepresent invention.

DETAILED DESCRIPTION

Please refer to FIG. 2, which is a schematic diagram of a touch sensorsystem 20 according to an embodiment of the present invention. As shownin FIG. 2, the touch sensor system 20 includes a touch panel 200, atouch controller 202 and a multiplexer (MUX) 204. The touch panel 200includes 16 touch sensing areas arranged in a 4×4 array. The touchcontroller 202, coupled to the MUX 204, is used for controlling touchdriving and sensing on the touch panel 200. The touch controller 202 maybe a touch control integrated circuit (IC) or other type of controlcircuit. The touch controller 202 may include a plurality of pinsconnected to the MUX 204 via a plurality of touch control wires and aplurality of touch sensing wires. Each pin may be connected to one ofthe plurality of touch control wires or one of the plurality of touchsensing wires. In this example, the touch controller 202 has 8 pinsconnected to the MUX 204, where 4 pins are connected with the touchcontrol wires S1-S4 and 4 pins are connected with the touch sensingwires AFE1-AFE4.

In detail, each of the touch sensing wires AFE1-AFE4 may transmitdriving signals from the touch controller 202 to the MUX 204. Thedriving signals are forwarded to the touch panel 200 to perform drivingon one of the touch sensing areas on the touch panel 200. The touchsensing wires AFE1-AFE4 then transmit sensing signals from the touchsensing areas to the touch controller 202.

Please keep referring to FIG. 2. The MUX 204 is coupled between thetouch panel 200 and the touch controller 202. In detail, the MUX 204 isconnected to the touch sensing areas on the touch panel 100 via 16connecting wires T11-T44, each of which is connected to one touchsensing area via a contact, as shown in FIG. 2. The MUX 204 includes aplurality of switches. In each of the switches, a first connectionterminal is coupled to the touch controller 202 via a touch sensingwire, a second connection terminal is coupled to a touch sensing area onthe touch panel 200, and a control terminal is coupled to a touchcontrol wire, for receiving a control signal from the touch controller202. In other words, each switch is connected between the touchcontroller 202 and one of the touch sensing areas, and receives acontrol signal from one of the touch control wires S1-S4. With theimplementation and connection of the switches in the MUX 204, the touchcontroller 202 is allowed to perform touch driving and sensing in aspecific order by triggering the touch control wires S1-S4 in an order,where the touch control wires S1-S4 may control different switches inthe MUX 204 to be open or closed.

Please note that several of the switches connected to specific touchsensing areas (e.g., a row or a column of touch sensing areas) mayreceive the same control signal from the same touch control wire, sothat the specific touch sensing areas may undergo touch driving andsensing simultaneously. In this manner, the touch sensing areas areallowed to undergo touch driving and sensing in a specific order such asrow by row or column by column.

An exemplary circuit structure of the MUX 204 is illustrated in FIG. 3.The MUX 204 includes 16 switches coupled to 16 touch sensing areas onthe touch panel 200 via the connecting wires T11-T44, respectively.These switches are further coupled to the touch controller 202 via thetouch sensing wires AFE1-AFE4. In detail, 4 switches respectivelyconnected to the connecting wires T11, T21, T31 and T41 on oneconnection terminal are connected to the touch sensing wire AFE1 onanother connection terminal, 4 switches respectively connected to theconnecting wires T12, T22, T32 and T42 on one connection terminal areconnected to the touch sensing wire AFE2 on another connection terminal,4 switches respectively connected to the connecting wires T13, T23, T33and T43 on one connection terminal are connected to the touch sensingwire AFE3 on another connection terminal, and 4 switches respectivelyconnected to the connecting wires T14, T24, T34 and T44 on oneconnection terminal are connected to the touch sensing wire AFE4 onanother connection terminal. Further, 4 switches respectively connectedto the connecting wires T11, T12, T13 and T14 are controlled by acontrol signal on the touch control wire S1, 4 switches respectivelyconnected to the connecting wires T21, T22, T23 and T24 are controlledby a control signal on the touch control wire S2, 4 switchesrespectively connected to the connecting wires T31, T32, T33 and T34 arecontrolled by a control signal on the touch control wire S3, and 4switches respectively connected to the connecting wires T41, T42, T43and T44 are controlled by a control signal on the touch control wire S4.In this manner, the touch driving and sensing operations on the firstcolumn of touch sensing areas on the touch panel 200 is controlled bythe touch control wire S1. The touch driving and sensing operations onthe second column of touch sensing areas on the touch panel 200 iscontrolled by the touch control wire S2. The touch driving and sensingoperations on the third column of touch sensing areas on the touch panel200 is controlled by the touch control wire S3. The touch driving andsensing operations on the fourth column of touch sensing areas on thetouch panel 200 is controlled by the touch control wire S4.

Please refer to FIG. 4, which is a waveform diagram of control signalson the touch control wires S1-S4. As shown in FIG. 4, the controlsignals are triggered in an order of S1, S2, S3 and S4 in time periodst1-t4. A control signal controls the switches to be open when it is in alower level, and controls the switches to be closed when it is in ahigher level. Please refer to FIG. 4 together with FIG. 3 for detaileddescriptions. In the time period t1, the control signal on the touchcontrol wire S1 is triggered, allowing the touch sensing wires AFE1-AFE4to be connected to the connecting wires T11, T12, T13 and T14,respectively. The touch controller 202 can thereby perform touch drivingand sensing on the first column of touch sensing areas on the touchpanel 200. In the time period t2, the control signal on the touchcontrol wire S2 is triggered, allowing the touch sensing wires AFE1-AFE4to be connected to the connecting wires T21, T22, T23 and T24,respectively. The touch controller 202 can thereby perform touch drivingand sensing on the second column of touch sensing areas on the touchpanel 200. In the time period t3, the control signal on the touchcontrol wire S3 is triggered, allowing the touch sensing wires AFE1-AFE4to be connected to the connecting wires T31, T32, T33 and T34,respectively. The touch controller 202 can thereby perform touch drivingand sensing on the third column of touch sensing areas on the touchpanel 200. In the time period t4, the control signal on the touchcontrol wire S4 is triggered, allowing the touch sensing wires AFE1-AFE4to be connected to the connecting wires T41, T42, T43 and T44,respectively. The touch controller 202 can thereby perform touch drivingand sensing on the fourth column of touch sensing areas on the touchpanel 200. The touch controller 202 and the MUX 204 then repeat theiroperations in time periods t5-t8, t9-t12, and so on. In this manner, thetouch controller 202 may control the MUX 204 to perform touch drivingand sensing on the touch sensing areas column by column. The touchdriving and sensing operations for the entire touch sensing areas can beaccomplished in 4 time periods.

Please note that according to the embodiments of the present invention,the pin number of the touch controller may be reduced. With aconventional wire connection method without the usage of any MUXs in theprior art, a touch panel having 16 touch sensing areas arranged in a 4×4array needs 16 connecting wires for the touch driving and sensingoperations on the touch sensing areas. Therefore, 16 I/O pins on thetouch IC is necessary. In contrast, in the embodiment shown in FIG. 2,the touch controller 202 has only 8 pins connected to the MUX 204, where4 pins are connected with the touch control wires S1-S4 and 4 pins areconnected with the touch sensing wires AFE1-AFE4. Note that the MUX 204may be an analog MUX fabricated on the glass substrate of the touchpanel 200 with a touch panel process. When the MUX 204 is implemented onthe glass substrate with the touch panel process, the touch controller202, which is usually implemented by a touch IC, only requires 8 I/Opins. The reduced pin number decreases the die size of the touch IC, andthereby reduces the cost. With the decreased pin number, there may bemore space for the bonding pitch in each I/O pin; this enhances the wirebonding quality of the touch IC.

In another embodiment, the touch controller 202 may also perform touchdriving and sensing on the touch sensing areas row by row. For example,please refer to FIG. 5, which is a schematic diagram of anotherexemplary circuit structure of the MUX 204. As shown in FIG. 5, the MUX204 also includes 16 switches coupled to 16 touch sensing areas on thetouch panel 200 via the connecting wires T11-T44, respectively. Theseswitches are further coupled to the touch controller 202 via the touchsensing wires AFE1-AFE4. In detail, 4 switches respectively connected tothe connecting wires T11, T12, T13 and T14 on one connection terminalare connected to the touch sensing wire AFE1 on another connectionterminal, 4 switches respectively connected to the connecting wires T21,T22, T23 and T24 on one connection terminal are connected to the touchsensing wire AFE2 on another connection terminal, 4 switchesrespectively connected to the connecting wires T31, T32, T33 and T34 onone connection terminal are connected to the touch sensing wire AFE3 onanother connection terminal, and 4 switches respectively connected tothe connecting wires T41, T42, T43 and T44 on one connection terminalare connected to the touch sensing wire AFE4 on another connectionterminal. Further, 4 switches respectively connected to the connectingwires T11, T21, T31 and T41 are controlled by a control signal on thetouch control wire S1, 4 switches respectively connected to theconnecting wires T12, T22, T32 and T42 are controlled by a controlsignal on the touch control wire S2, 4 switches respectively connectedto the connecting wires T13, T23, T33 and T43 are controlled by acontrol signal on the touch control wire S3, and 4 switches respectivelyconnected to the connecting wires T14, T24, T34 and T44 are controlledby a control signal on the touch control wire S4. In this manner, thetouch driving and sensing operations on the first row of touch sensingareas on the touch panel 200 is controlled by the touch control wire S1.The touch driving and sensing operations on the second row of touchsensing areas on the touch panel 200 is controlled by the touch controlwire S2. The touch driving and sensing operations on the third row oftouch sensing areas on the touch panel 200 is controlled by the touchcontrol wire S3. The touch driving and sensing operations on the fourthrow of touch sensing areas on the touch panel 200 is controlled by thetouch control wire S4.

Please refer to FIG. 5 together with FIG. 4 for detailed descriptions.In the time period t1, the control signal on the touch control wire S1is triggered, allowing the touch sensing wires AFE1-AFE4 to be connectedto the connecting wires T11, T21, T31 and T41, respectively. The touchcontroller 202 can thereby perform touch driving and sensing on thefirst row of touch sensing areas on the touch panel 200. In the timeperiod t2, the control signal on the touch control wire S2 is triggered,allowing the touch sensing wires AFE1-AFE4 to be connected to theconnecting wires T12, T22, T32 and T42, respectively. The touchcontroller 202 can thereby perform touch driving and sensing on thesecond row of touch sensing areas on the touch panel 200. In the timeperiod t3, the control signal on the touch control wire S3 is triggered,allowing the touch sensing wires AFE1-AFE4 to be connected to theconnecting wires T13, T23, T33 and T43, respectively. The touchcontroller 202 can thereby perform touch driving and sensing on thethird row of touch sensing areas on the touch panel 200. In the timeperiod t4, the control signal on the touch control wire S4 is triggered,allowing the touch sensing wires AFE1-AFE4 to be connected to theconnecting wires T14, T24, T34 and T44, respectively. The touchcontroller 202 can thereby perform touch driving and sensing on thefourth row of touch sensing areas on the touch panel 200. The touchcontroller 202 and the MUX 204 then repeat their operations in timeperiods t5-t8, t9-t12, and so on. In this manner, the touch controller202 may control the MUX 204 to perform touch driving and sensing on thetouch sensing areas row by row. The touch driving and sensing operationsfor the entire touch sensing areas can be accomplished in 4 timeperiods.

Please note that the present invention provides a circuit structure of atouch sensor system having a MUX disposed between the touch controllerand the touch panel. The pin number of the touch controller cantherefore be reduced with the MUX implemented on the glass substrate ofthe touch panel. Those skilled in the art can make modifications andalternations accordingly. For example, as shown in the aboveembodiments, the connections of the switches in the MUX may be arrangedin a specific manner to perform touch driving and sensing row by row orcolumn by column. In another embodiment, the touch driving and sensingoperations may be performed by other methods. For example, the secondcolumn of touch sensing areas may undergo touch driving and sensingbefore the first column of touch sensing areas, or the third row oftouch sensing areas may undergo touch driving and sensing next to thefirst row of touch sensing areas. Alternatively, the touch driving andsensing operations may be performed on the touch sensing areas in anypossible orders other than the row-by-row and column-by-column manners.In addition, the circuit structure of the touch panel 200 and the MUX204 shown in FIG. 2 is only one of various possible implementations. Forexample, in the touch panel 200 shown in FIG. 2, each of the connectingwires T11-T44 extends from the MUX 204 to the upper side of the touchpanel 200 and has the same length. This arrangement allows each of theconnecting wires T11-T44 to have similar resistance-capacitance (RC)characteristics. In another embodiment, the connecting wires T11-T44 mayhave different lengths, as long as each of the connecting wires T11-T44is long enough to connect with the corresponding touch sensing area.Furthermore, there is only one MUX 204 in the embodiment shown in FIG.2, but in another embodiment, there may be more than one MUX disposedbetween the touch panel and the touch controller.

For example, please refer to FIG. 6, which is a schematic diagram ofanother touch sensor system 60 according to an embodiment of the presentinvention. As shown in FIG. 6, the circuit structure of the touch sensorsystem 60 is similar to that of the touch sensor system 20; hence,circuit elements and signals having similar functions are denoted by thesame symbols. A main difference between the touch sensor system 60 andthe touch sensor system 20 is that the touch sensor system 60 has twoMUXs 604_1 and 604 ₁₃ 2 while the touch sensor system 20 has only oneMUX 204. The touch sensor system 60 also includes 16 touch sensing areasarranged in a 4×4 array, and each of the touch sensing areas areconnected to the MUX 604_1 or 604_2 via 16 connecting wires T11-T44,respectively. More specifically, the connecting wires T11, T12, T13,T14, T21, T22, T23 and T24 connect the touch sensing areas located onthe left half of the touch panel 200 to the MUX 604_1, and theconnecting wires T31, T32, T33, T34, T41, T42, T43 and T44 connect thetouch sensing areas located on the right half of the touch panel 200 tothe MUX 604_2. The MUX 604_1 is further connected to the touchcontroller 202 via touch control wires S1_L and S2_L and touch sensingwires AFE1_L-AFE4_L. The MUX 604_2 is further connected to the touchcontroller 202 via touch control wires S1_R and S2_R and touch sensingwires AFE1_R-AFE4_R. In this case, the touch controller 202 has totally12 pins connected to the MUXs 604_1 and 604_2, where 4 pins areconnected with the touch control wires S1_L, S2_L, S1_R and S2_R, and 8pins are connected with the touch sensing wires AFE1_L-AFE4_L andAFE1_R-AFE4_R. In this case, the pin number of the touch controller 202is still fewer than that in the prior art.

Please refer to FIGS. 7A and 7B for detailed circuit structures of theMUXs 604_1 and 604_2. As shown in FIG. 7A, the MUX 604_1 includes 8switches coupled to 8 touch sensing areas on the left half of the touchpanel 200 via the connecting wires T11, T12, T13, T14, T21, T22, T23 andT24, respectively. These switches are further coupled to the touchcontroller 202 via the touch sensing wires AFE1_L-AFE4_L. In detail, 2switches respectively connected to the connecting wires T11 and T21 onone connection terminal are connected to the touch sensing wire AFE1_Lon another connection terminal, 2 switches respectively connected to theconnecting wires T12 and T22 on one connection terminal are connected tothe touch sensing wire AFE2_L on another connection terminal, 2 switchesrespectively connected to the connecting wires T13 and T23 on oneconnection terminal are connected to the touch sensing wire AFE3_L onanother connection terminal, and 2 switches respectively connected tothe connecting wires T14 and T24 on one connection terminal areconnected to the touch sensing wire AFE4 L on another connectionterminal. Further, 4 switches respectively connected to the connectingwires T11, T12, T13 and T14 are controlled by a control signal on thetouch control wire S1_L, and 4 switches respectively connected to theconnecting wires T21, T22, T23 and T24 are controlled by a controlsignal on the touch control wire S2_L. In this manner, the touch drivingand sensing operations on the first column of touch sensing areas on thetouch panel 200 is controlled by the touch control wire S1_L. The touchdriving and sensing operations on the second column of touch sensingareas on the touch panel 200 is controlled by the touch control wire S2L.

As shown in FIG. 7B, the MUX 604_2 includes 8 switches coupled to 8touch sensing areas on the right half of the touch panel 200 via theconnecting wires T31, T32, T33, T34, T41, T42, T43 and T44,respectively. These switches are further coupled to the touch controller202 via the touch sensing wires AFE1_R-AFE4_R. In detail, 2 switchesrespectively connected to the connecting wires T31 and T41 on oneconnection terminal are connected to the touch sensing wire AFE1_R onanother connection terminal, 2 switches respectively connected to theconnecting wires T32 and T42 on one connection terminal are connected tothe touch sensing wire AFE2_R on another connection terminal, 2 switchesrespectively connected to the connecting wires T33 and T43 on oneconnection terminal are connected to the touch sensing wire AFE3 R onanother connection terminal, and 2 switches respectively connected tothe connecting wires T34 and T44 on one connection terminal areconnected to the touch sensing wire AFE4_R on another connectionterminal. Further, 4 switches respectively connected to the connectingwires T31, T32, T33 and T34 are controlled by a control signal on thetouch control wire S1_R, and 4 switches respectively connected to theconnecting wires T41, T42, T43 and T44 are controlled by a controlsignal on the touch control wire S2_R. In this manner, the touch drivingand sensing operations on the third column of touch sensing areas on thetouch panel 200 is controlled by the touch control wire S1_R. The touchdriving and sensing operations on the fourth column of touch sensingareas on the touch panel 200 is controlled by the touch control wireS2_R.

Please refer to FIG. 8, which is a waveform diagram of control signalson the touch control wires S1_L, S2_L, S1_R and S2_R. As shown in FIG.8, the control signals are triggered in an order of S1_L, S2_L, S1_R andS2_R in time periods t1-t4. A control signal controls the switches to beopen when it is in a lower level, and controls the switches to be closedwhen it is in a higher level. Please refer to FIG. 8 together with FIGS.7A and 7B for detailed descriptions. In the time period t1, the controlsignal on the touch control wire S1_L is triggered, allowing the touchsensing wires AFE1_L-AFE4_L to be connected to the connecting wires T11,T12, T13 and T14, respectively. The touch controller 202 can therebyperform touch driving and sensing on the first column of touch sensingareas on the touch panel 200. In the time period t2, the control signalon the touch control wire S2_L is triggered, allowing the touch sensingwires AFE1_L-AFE4_L to be connected to the connecting wires T21, T22,T23 and T24, respectively. The touch controller 202 can thereby performtouch driving and sensing on the second column of touch sensing areas onthe touch panel 200. In the time period t3, the control signal on thetouch control wire S1_R is triggered, allowing the touch sensing wiresAFE1_R-AFE4_R to be connected to the connecting wires T31, T32, T33 andT34, respectively. The touch controller 202 can thereby perform touchdriving and sensing on the third column of touch sensing areas on thetouch panel 200. In the time period t4, the control signal on the touchcontrol wire S2_R is triggered, allowing the touch sensing wiresAFE1_R-AFE4_R to be connected to the connecting wires T41, T42, T43 andT44, respectively. The touch controller 202 can thereby perform touchdriving and sensing on the fourth column of touch sensing areas on thetouch panel 200. The touch controller 202 and the MUXs 604_1 and 604_2then repeat their operations in time periods t5-t8, t9-t12, and so on.In this manner, the touch controller 202 may control the MUXs 604_1 and604_2 to perform touch driving and sensing on the touch sensing areascolumn by column. The touch driving and sensing operations for theentire touch sensing areas can be accomplished in 4 time periods.

In another embodiment, in a touch sensor system having at least twoMUXs, the touch driving and sensing may be performed on at least twocolumns or two rows of touch sensing areas simultaneously.

Therefore, the touch controller may control the MUXs to perform touchdriving and sensing on at least two columns or two rows of touch sensingareas simultaneously by triggering control signals on different touchcontrol wires simultaneously. In this manner, the touch driving andsensing operations may be performed in a faster speed, so that theperformance of the touch sensor system may be enhanced.

For example, please refer to FIG. 9, which is a waveform diagram ofcontrol signals on the touch control wires S1_L, S2_L, S1_R and S2_Raccording to another embodiment of the present invention. As shown inFIG. 9, the control signals on the touch control wires S1_L and S1_R aretriggered simultaneously, and the control signals on the touch controlwires S2_L and S2_R are trigger simultaneously. In such a situation, inthe time period t1, the control signals on the touch control wires S1_Land S1_R are triggered; this allows the touch sensing wiresAFE1_L-AFE4_L to be connected to the connecting wires T11, T12, T13 andT14, respectively, and allows the touch sensing wires AFE1_R-AFE4_R tobe connected to the connecting wires T31, T32, T33 and T34,respectively. The touch controller 202 can thereby perform touch drivingand sensing on the first and third columns of touch sensing areas on thetouch panel 200 simultaneously. In the time period t2, the controlsignals on the touch control wires S2_L and S2_R are triggered; thisallows the touch sensing wires AFE1_L-AFE4_L to be connected to theconnecting wires T21, T22, T23 and T24, respectively, and allows thetouch sensing wires AFE1_R-AFE4_R to be connected to the connectingwires T41, T42, T43 and T44, respectively. The touch controller 202 canthereby perform touch driving and sensing on the second and fourthcolumns of touch sensing areas on the touch panel 200 simultaneously.The touch controller 202 and the MUXs 604_1 and 604_2 then repeat theiroperations in time periods t3-t4, t5-t6, and so on. In this manner, thetouch controller 202 may control the MUXs 604_1 and 604_2 to performtouch driving and sensing on two columns of touch sensing areassimultaneously. The touch driving and sensing operations for the entiretouch sensing areas can be accomplished in 2 time periods. As a result,the speed of touch driving and sensing operations can be increased.

Based on the above embodiments and illustrations shown in FIGS. 2-9,those skilled in the art can derive the operations of performing touchdriving and sensing on at least two rows of touch sensing areassimultaneously. The detailed operations will not be narrated herein.

Please note that the operational speed of touch driving and sensing canbe increased with an increasing number of MUXs. For example, if thereare 4 MUXs in a touch sensor system, there may be 4 columns or 4 rows oftouch sensing areas undergoing touch driving and sensing operationssimultaneously. However, the increasing number of MUXs may be followedby an increasing number of I/O pins in the touch controller. Thoseskilled in the art are allowed to make a selection between a higheroperational speed and fewer number of I/O pins according to systemrequirements. Therefore, the circuit structure and wire connection ofthe MUX(s) may be arranged to realize any possible orders of touchdriving and sensing operations; this should not be limited herein.

Please refer to FIG. 10, which is a schematic diagram of a touch sensorsystem 1000 according to an embodiment of the present invention. Asshown in FIG. 10, the touch sensor system 1000 includes a touch panel1100, a touch controller 1002 and MUXs 1004_1 and 1004_2. The touchpanel 1100 is a large touch panel having 576 touch sensing areasarranged in a 32×18 array, i.e., there are 32 rows and 18 columns oftouch sensing areas. These touch sensing areas are connected to the MUXs1004_1 or 1004_2 via 576 connecting wires T01_01-T18_32, respectively.More specifically, the connecting wires T01_01-T09_32 connect the touchsensing areas located on the left half of the touch panel 1100 to theMUX 1004_1, and the connecting wires T10_01-T18_32 connect the touchsensing areas located on the right half of the touch panel 1100 to theMUX 1004_2. The MUX 1004_1 is further connected to the touch controller1002 via touch control wires S1_L-S9_L and touch sensing wiresAFE1_L-AFE32_L. The MUX 1004_2 is further connected to the touchcontroller 1002 via touch control wires S1_R-S9_R and touch sensingwires AFE1_R-AFE32_R.

Please refer to FIGS. 11A and 11B for detailed circuit structures of theMUXs 1004_1 and 1004_2. As shown in FIG. 11A, the MUX 1004_1 includes9×32 switches coupled to 288 touch sensing areas on the left half of thetouch panel 1100 via the connecting wires T01_01-T09_32, respectively.These switches are further coupled to the touch controller 1002 via thetouch sensing wires AFE1_L-AFE32_L. In detail, 9 switches respectivelyconnected to the connecting wires T01_01-T09_01 on one connectionterminal are connected to the touch sensing wire AFE1_L on anotherconnection terminal, 9 switches respectively connected to the connectingwires T01_02-T09_02 on one connection terminal are connected to thetouch sensing wire AFE2_L on another connection terminal, and so on.Finally, 9 switches respectively connected to the connecting wiresT01_32-T09_32 on one connection terminal are connected to the touchsensing wire AFE32_L on another connection terminal. Further, 32switches respectively connected to the connecting wires T01_01-T01_32are controlled by a control signal on the touch control wire S1_L, 32switches respectively connected to the connecting wires T02_01-T02_32are controlled by a control signal on the touch control wire S2_L, andso on. Finally, 32 switches respectively connected to the connectingwires T09_01-T09_32 are controlled by a control signal on the touchcontrol wire S9_L. In this manner, the touch driving and sensingoperations on the first to ninth columns of touch sensing areas on thetouch panel 1100 are controlled by the touch control wires S1_L-S9_L,respectively.

As shown in FIG. 11B, the MUX 1004_2 includes 9×32 switches coupled to288 touch sensing areas on the right half of the touch panel 1100 viathe connecting wires T10_01-T18_32, respectively. These switches arefurther coupled to the touch controller 1002 via the touch sensing wiresAFE1_R-AFE32_R. In detail, 9 switches respectively connected to theconnecting wires T10_01-T18_01 on one connection terminal are connectedto the touch sensing wire AFE1_R on another connection terminal, 9switches respectively connected to the connecting wires T10_02-T18_02 onone connection terminal are connected to the touch sensing wire AFE2 Ron another connection terminal, and so on. Finally, 9 switchesrespectively connected to the connecting wires T10_32-T18_32 on oneconnection terminal are connected to the touch sensing wire AFE32_R onanother connection terminal. Further, 32 switches respectively connectedto the connecting wires T10_01-T10_32 are controlled by a control signalon the touch control wire S1_R, 32 switches respectively connected tothe connecting wires T11_01-T11_32 are controlled by a control signal onthe touch control wire S2_R, and so on. Finally, 32 switchesrespectively connected to the connecting wires T18_01-T18_32 arecontrolled by a control signal on the touch control wire S9_R. In thismanner, the touch driving and sensing operations on the tenth toeighteenth columns of touch sensing areas on the touch panel 1100 arecontrolled by the touch control wires S1_R-S9_R, respectively.

Please refer to FIG. 12, which is a waveform diagram of control signalson the touch control wires S1_L-S9_L and S1_R-S9_R. As shown in FIG. 12,the control signals on the touch control wires S1_L and S1_R aretriggered simultaneously, and the control signals on the touch controlwires S2_L and S2_R are trigger simultaneously, and so on. In such asituation, in the time period t1, the control signals on the touchcontrol wires S1_L and S1_R are triggered; this allows the touch sensingwires AFE1_L-AFE32_L to be connected to the connecting wiresT01_01-T01_32, respectively, and allows the touch sensing wiresAFE1_R-AFE32_R to be connected to the connecting wires T10_01-T10_32,respectively. The touch controller 1002 can thereby perform touchdriving and sensing on the first and tenth columns of touch sensingareas on the touch panel 1100 simultaneously. In the time period t2, thecontrol signals on the touch control wires S2_L and S2_R are triggered;this allows the touch sensing wires AFE1_L-AFE32_L to be connected tothe connecting wires T02_01-T02_32, respectively, and allows the touchsensing wires AFE1_R-AFE32_R to be connected to the connecting wires TT11_01-T11_32, respectively. The touch controller 1002 can therebyperform touch driving and sensing on the second and eleventh columns oftouch sensing areas on the touch panel 1100 simultaneously. Thoseskilled in the art should be able to derive the operations in timeperiods t3-t9 according to the above descriptions and the illustrationsin FIGS. 11A, 11B and 12; these will not be narrated herein. The touchcontroller 1002 and the MUXs 1004_1 and 1004_2 then repeat theiroperations after the time period t9. In this manner, the touchcontroller 1002 may control the MUXs 1004_1 and 1004_2 to perform touchdriving and sensing on two columns of touch sensing areassimultaneously. The touch driving and sensing operations for the entiretouch sensing areas can be accomplished in 9 time periods.

Please note that, since the control signals on the touch control wiresS1_L-S9_L and S1_R-S9_R can be triggered simultaneously, the touchcontrol wires S1_L-S9_L can be connected to the touch control wiresS1_R-S9_R, respectively, in order to save the pin number, as shown inFIG. 10. In such a situation, the touch controller 1002 has 9 pinsconnected to the touch control wires S1_L-S9_L and S1_R-S9_R. Therefore,in the embodiment shown in FIG. 10, the touch controller 1002 hastotally 73 pins connected to the MUXs 1004_1 and 1004_2, where 9 pinsare connected with the touch control wires S1_L-S9_L and S1_R-S9_R and64 pins are connected with the touch sensing wires AFE1_L-AFE32_L andAFE1_R-AFE32_R. In contrast to the prior art where a touch IC for atouch panel having touch sensing areas arranged in a 32×18 arrayrequires 576 I/O pins, the embodiment of the present invention mayreduce the pin number to 73. This significant reduction of pin numberleads to tremendous benefits of cost saving and bonding qualityimprovement.

The abovementioned operations of the touch controllers 202 and 1002 maybe summarized into a process 130, as shown in FIG. 13. The process 130may be applied to a touch controller of a touch sensor system having aplurality of MUXs, for reducing the pin number of the touch controller.The process 130 includes the following steps:

Step 1300: Start.

Step 1302: Sequentially trigger a plurality of control signals to aplurality of touch control wires of the MUXs.Step 1304: Receive a plurality of touch sensing signals from the MUXs tothe touch controller.

Step 1306: End.

The detailed operations and alternations of the process 130 areillustrated in the above descriptions, and will not be narratedhereinafter.

To sum up, the present invention provides a touch sensor system with aMUX disposed between the touch controller and the touch panel, forreducing the pin number of the touch controller. The MUX may be ananalog MUX fabricated on the glass substrate of the touch panel with atouch panel process. Therefore, the pin number of the touch controller,which is usually implemented by a touch IC, can be significantlyreduced. The reduced pin number decreases the die size of the touch IC,and thereby reduces the cost. With the decreased pin number, there maybe more space for the bonding pitch in each I/O pin; this enhances thewire bonding quality of the touch IC. Further, the touch sensor systemmay include more than one MUX, where at least two columns or two rows oftouch sensing areas may undergo touch driving and sensingsimultaneously. This increases the speed of touch driving and sensingoperations.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A touch sensor system, comprising: a touch panel,comprising a plurality of touch sensing areas; at least one multiplexer,coupled to the plurality of touch sensing areas on the touch panel; anda touch controller, coupled to the at least one multiplexer, forcontrolling touch driving and sensing on the touch panel, the touchcontroller comprising a plurality of pins connected to the at least onemultiplexer via a plurality of touch control wires and a plurality oftouch sensing wires, wherein each of the plurality of pins is connectedto one of the plurality of touch control wires or one of the pluralityof touch sensing wires; wherein each of the plurality of touch sensingwires transmits driving signals from the touch controller to acorresponding multiplexer among the at least one multiplexer to performdriving on one of the plurality of touch sensing areas, and transmitssensing signals from the touch sensing area to the touch controller;wherein the touch controller controls the at least one multiplexer toperform touch driving and sensing on the plurality of touch sensingareas in a specific order by triggering the plurality of touch controlwires in an order.
 2. The touch sensor system of claim 1, wherein eachof the at least one multiplexer comprises a plurality of switches. 3.The touch sensor system of claim 2, wherein each of the plurality ofswitches is connected between the touch controller and one of theplurality of touch sensing areas, and receives a control signal from oneof the plurality of touch control wires.
 4. The touch sensor system ofclaim 2, wherein several of the plurality of switches connected tospecific touch sensing areas among the plurality of touch sensing areasreceive a control signal from a same touch control wire among theplurality of touch control wires, allowing the specific touch sensingareas to undergo touch driving and sensing simultaneously.
 5. The touchsensor system of claim 1, wherein the at least one multiplexer isfabricated with a touch panel process.
 6. The touch sensor system ofclaim 1, wherein the touch controller controls the at least onemultiplexer to perform touch driving and sensing on the plurality oftouch sensing areas row by row or column by column by triggering controlsignals on the plurality of touch control wires.
 7. The touch sensorsystem of claim 6, wherein a plurality of switches of the at least onemultiplexer connected to a same row or a same column of touch sensingareas among the plurality of touch sensing areas receive a controlsignal from a same touch control wire among the plurality of touchcontrol wires, allowing the plurality of touch sensing areas to undergotouch driving and sensing row by row or column by column.
 8. The touchsensor system of claim 1, wherein the touch controller controls the atleast one multiplexer to perform touch driving and sensing on at leasttwo columns of the plurality of touch sensing areas simultaneously or atleast two rows of the plurality of touch sensing areas simultaneously bytriggering control signals on different touch control wires among theplurality of touch control wires simultaneously.
 9. The touch sensorsystem of claim 8, wherein the at least one multiplexer comprises atleast two multiplexers simultaneously receive a control signal, allowingthe touch controller to perform touch driving and sensing on the atleast two columns of the plurality of touch sensing areas simultaneouslyor the at least two rows of the plurality of touch sensing areassimultaneously.
 10. A multiplexer used in a touch sensor system, forreducing a pin number of a touch controller of the touch sensor system,the touch controller connected to the multiplexer via a plurality oftouch control wires and a plurality of touch sensing wires, themultiplexer comprising: a plurality of switches, each of whichcomprising: a first connection terminal, coupled to the touch controllervia one of the plurality of touch sensing wires; a second connectionterminal, coupled to a touch panel of the touch control system, thetouch panel comprising a plurality of touch sensing areas; and a controlterminal, coupled to one of the plurality of touch control wires, forreceiving one of a plurality of control signals from the touchcontroller; wherein several of the plurality of switches connected tospecific touch sensing areas among the plurality of touch sensing areasreceive one of the plurality of control signals from a same touchcontrol wire among the plurality of touch control wires via the controlterminal.
 11. A method of reducing a pin number of a touch controller ofa touch sensor system, the touch sensor system comprising a plurality ofmultiplexers coupled between the touch controller and a touch panel, themethod comprising: sequentially triggering a plurality of controlsignals to a plurality of touch control wires of the multiplexers; andreceiving a plurality of touch sensing signals from the multiplexers tothe touch controller.
 12. The method of claim 11, wherein one of thetouch sensing signals corresponds to specific touch sensing areas of thetouch panel.